The oldschool telephone model has two main complexities:
- the chord (which I’m still struggling with)
- the dial
In order to get the dial right you have to start with the holes first. If you start from the main dial disk and cutout the holes after, blender starts to mess your topology. Example here:
You have to start from the holes and create the first meshes around these holes in order to duplicate the set around a central empty:
Once duplicated in order to form the outside dial you can join all duplicated elements and clean up the duplicate vertices. The last step is to select the inner edge to extrude it inwards to fill the center of the dial.